chicago



, STATES PATENT M.I o'iiir mOksON, ooHrcAeo, ILLINOIs, AssIGNoa To AUTOMATIC -annoiata;V

OIIIQAGO, ILLINOIS, .AHOORPORATION or ILLINOIS. y r

RELAY.

originaria. 1,330,020, dated citienzof the United States of America, and 'a' resident of Chicago', county of Cook, and

vState of Illinois, have invented certain newl and useful Improvements in Relays, otV

Y which the following is a specification.

hy invention relates to electromagnetic i circuit closing devices, and more yspecifically 'to a relay for closing any kind of a circuit.

One of the objects of my invention is to provide a relay which may be connected in circuit with sources of either alternating or direct current and which may be arranged to operate withthe direct current only or with alternating current only, or which may operate in a particular manner with both alternating current and direct current.

Another object of my invention is to proy vide a relay whichutilizes the xvlheatstone bridge vprinciple as applied to magnetic flux rather than to electric current and in which the armature-of said relay forms the bridge across the arms of a Wheatstone bridge corresponding to ythe receiver or galvanometer bridge. v f another .object of myn invention is to provide a relay which may be connected in circuit with a direct current and which will attract. its armature momentarily when the circuit is closed and again only momentarily when the circuit is broken. y

My invention is adapted for various uses such asin a telephone system in which a relay is desired which will not operate with ringingr current but which'willoperate with direct or operating current. Also in power work such a device may be used to. great advantage. y

Other features and objects of my invention will be pointed out in the specification by referring to the accompanying drawings in Which- Figure lshows one form of my improved relay.

Fig. 2 1s an end view .of vthe relay shown in Fig. 1 takenfrom the' left of said figure.

' Fig. 3 is a top view of the relay in Fig: 1. Fig. 4 shows another form of my improved relay, and F igs. 5 and 6 are1 respectively, an end view and a top view of' the relay shownin Fig. 4.

- I will now describe my inventlon more 1n Specification of Reissued Letters Patent. Reissued fxljl', 6, 1920.

February 3, 1920, Serial No. 206,318, led December 8, A1917. Application for reissue filed March 1, 1920. Serial No. 362,346.

detail. A Referring to Figs. 1,v 2`and 3, I have shown a coil 2 mounted upon an iron mounting bracket 3 at one end by' mea-ns of the' screw 5, and having another iron pole piece 4 lirmlyvsecured to the other end thereotI by means of the screw 6. The coil 2 has a pair :of terminals 7 and 8 to whichA any desired circuit may be connected. F'irmly mounted. between the upper extending ends of the brackets 3 and 1i' are a pair of parallel soft iron cores or'rods 9 and .10, which are secured .by iron screws to the two brackets 3 and 4.-'. On therighthand end of the core 9 is firmly attached a copper slug 11 and on the left hand end of the core 10 is secured another copper slug 12. These tivo copper slugs are mounted far enough apart to leave space for the armature 13 4which is pivoted vat the points 14; and 15 and yheldnormally awayrfrom the cores 9 and 10 by meansI of the coil spring 1 6, 'thereby maintaining a pair of springs 17 and 18 normally out of contact. At certain times to be pointed out hereinafter. the pole pieces 9 and 10 will be charged as opposite poles'pieces and will therefore attract the armature 13 to close the contact of springs 17 and 1S.

The relay which I have" described and which is shown in Figs'. 1, 2 and 3 is designed so that the armature 13 will be attracted only when alternating currersi' is iiowing through the coil 2. Also the arinature 1 3 will be attracted momentarily whenever a direct current is applied to the coil 2. and will again be momentaril.Y vattracted when the direct current is removed from the circuit of said coil. It will be seen that the .path of the magnetic flux caused by applying a direct current tothe winding of the coil 2 includes the core of said coil', thebracket 3, the cores 9 and 1() in multiple,

the heel piece 4, and back to the core of` coil 2. As is Awell known in the art. the copper slugs 11 and 12 vhave'a retarding action which acts against any change.' in the posed at two places, that i's, the flux in the vright hand end of the core 9 Will-be opposed by the counter force set up in the slug 11, and the magnetic flux in the core will be opposed in the-left hand end of saidcore by the 'counter act-ion of the slug y 12. Thus it will be seen that-the mid' points of the'cores 9 and 10 will actas north and south magnetic poles and cause the' armature 13 to be attracted-to said mid points, thereby short circuiting magnetically the two slugs. 11 and 12. The magnetic flux Will. now fiow from the core of coil 2, bracket 3, coil 10,v to the mid point thereof, armature 13, and on through the lett hand half of core 9, and through pole pece'4 -to the. core-'of coil 2.' As soon, however, as the magnetic flux in the two cores 9l and 10 has reached its vmaximum point and the counter force generated in theslugs 11 and 12 dies down, the cores 9 and'10 will form a free path to the flux vand the armature 13 will fall back. In the same .manner when the direct current circuit through the lcoil 2.is opened the 'slugs 11 and l2 will again oppose the decrease in flux in the two cores9 and 10 and the armature 13 will again be momentarily' attracted.' by the counter magnetic force generated therein. It will be seen that I have utilized the lVheatstone bridge principle as applied to iux rather than electric current batterybridge, the left hand end of the core 10 and the right hand endA of the core 9 ac t as the variable arms and the right hand end of .the core, 10 and the left hand end of the core 9. act as the fixed arms of said bridge, while the armature 13 acts as the receiver or galvanometer arm. Therefore when the two variable arms are changed in resistance relative to the fixed arms by the counter action of the slugs, a pull is exerted on the armature 13. f

Now, when an alternating current is supplied to the winding of the coil 2 it will be seen that, as the alternating current is continually changing in direction, the magnetic flux in the cores 9 and 10 will never be steady and therefore the count-er force in each slug 11 and l2 which is caused by'a change in the iiux of the cores 9 and 10, will be maintained constant and the armature .13 will therefore be held in its attracted position.

In Figs; 4,"5 and 6 I have shown another form of my improved relay vwhich acts in a much different manner. This relay is designed to be slow to energize when direct current is applied thereto and quick to deenergize when the direct current is removed.

-Also this relay is not responsive to alternating current. In Figs. 4, 5 and 6 I have shown a relay which is very similar to the relay shown in Figs. 1, 2 and 3, except that its -armature is pivoted in a different manner so as to respond to direct current. In these figures a coil 19 is shown mounted on a heel piece 20. Fir-mly secured to the upper end of this heel piece are avpairv'of a tail piece 2T which extends vback to the mid point of the cores 22 and 23 and is normally held against vsaid cores by the.

spring 2,9, which, therefore, also holds the armature 21 away from the core of the coil 19. This relay will operate in thel following manner. lVhen direct current is applied to the coil 19 alux will be generated which follows a path from the core of coil 19 through heel piece 20, cores 22 and 23 in parallel,`through the armature 21 and back to the core of said coil. The armature 21 will not be attracted at once, however, due

to the'pull which is exerted on the tail piece' 2T, which is held against the cores 22 and -23 unt-il the counter action of the slugs, 24

and 25 Ais overcome,in the same manner in which the armature 13, Fig. 1, was attracted, at which time the force exerted on the tail piece 2T will dieA out and the armature 21 will pull up and close the contact of springs 28 and 29 to close any desired circuit. Now and that the coil 2 and its core act as the ture 21 will not have a chance to pull up.

Therefore it will be seen that I have devlsed a very eiiicient and novel relay which 1s adapted for many uses and which may `be arranged to close an alarm circuit or sig` nal circuit momentarily when a direct vcurrent clrcuit 1s closed and agan..l when 1t 1s opened and which will not hold up on direct current.

Also it may be used when it is desired to have a relay which will be slow to Ienergize with vdirect current and which will not energize with alternating current.

Having fully described my invention what I desire to protect and secure by Letters Patent will be pointed out Kin the appended claims. l

That I claimas my invention is:

1. In a relay, a magnet, an armature for said magnet, means Jfor applying direct and alternating current to said magnet, means for-preventing said armature from being attracted when alternating current is applied to said magnet. means for causing said armatureto be slow in pulling up when dif rect current is rapplied to said magnet and means for causing said armature to fall back quickly when said direct current is removed.

2. In a relay, a magnet, an armature for said magnet pivoted at one point and having two arms extending therefrom at right anglesto each other, means for applying lcurrents of different characters to said magsaid net, means for attracting said armature in one 'direction when current of one character is applied and in the other direction when current ot another character is-ap- `plied to said magnet.

` 3. In a relay, aunagnet, an'armature for said magnet pivoted at one point and haying two arms extending in two directions therefrom, means for anlvinff alternatimT e E: t*

and direct current to said magnet, means for attracting one of said arms when alternating current is applied tosaid magnet and for attracting the other of said arms when direct currentis applied to said magnet.

4. In a relay, a magnet,an armature for said magnet, means for applying direct and alternating current to said magnet, means for preventing `said armature from being attracted when `alternating current is applied to said magnet, means for causing said armature to be slow in pulling up when dir ectcurrent is applied to said magnet, means for causing said armature to fall back quickly when said direct current is removed, anda circuit controlled by said relay.

5. In a relay, a magnet, an armature for said magnet pivoted atone point .and having two arms extending therefrom at right angles to each other. means for applying Icurrents ofdiiferent characters to said magnet, means for attracting said armature in one direction when current of one character is applied and in the other direction when current of another character is applied to said magnet, and a circuitcontrolled by said relay.

6. In a relay. a magnet,'a'n armature for 'said magnet pivoted at one point .having two arms extending in two directions therefrom, means for applying alternating and direct current t`o said magnet, means for attracting one of. said arms when alternating current is applied to said magnet and for attracting the other of said arms when direct current is applied-to said magnet, and

a circuit controlledby said relay.

7. In a relay, a magnet, an armature for magnet pivoted at one point and having two'arms extending therefrom at right angles to each orher,means for applying currents of different characters to said magnet, means for attracting said armature in one direction. when current of one character is applied and in 'the other direction when current of another character' is applied to said magnet. land' a circuit controlled by only one of said operations.

8. In a relay. a magnet, an armature for said magnet piroted at one point having tivo arms extending in two directions therefrom. means for applying alternating and direct current to said magnet, means for attracting one of said arms when alternating current is appied to said magnet and for' attracting the other of said arms when dicrations.

9. In a relay, a magnet, a magnetic circuit for said Inagnet' vhaving parallel branches, an armature for said magnet` parallel branches, `said bridged across said branches'at times short circuitingsaid ar-"f, mature magnetically, kand means forA re- `v moving said short ycircuitto cause "said ar'- mature to be attracted. i l l0. In `a`relay, a magnet, a'magnetic ci r' cuit for said magnet, said magnetic circuit pair of permanent arms and a' lpair of variable arms, an armaturev for said magnet said armature bridged across the points be?` permanent arms,`

tween the 'variable andy comprising a lVheat-stone"bridge'having 80 means for causing a magnetic flux to How inl said circuit', means for varyingthe 're' luctance of said variable arms, to cause the magnetic fiux to flow through said armature and attract` the same.v

y11. In a relay, cuit for said magnet, lsaid magnetic circuit comprising a VVheatstone bridge having a pair of permanent arms and a pair of variable arms, an armature for said magnet, said armature bridged across the points between the ,variable and permanent arms, means vfor causing a magnetic flux to flow in said circuit, means for Varying the reluctance of said variable arms, yto cause the magnetic flux to 'flow through said armature and attract thesame.

l2. Anl Velectromagnet having a magnetic circuit, a port-ion of said magnetic circuit comprising a' Viheatstonebridge having two arms which are of low reluctance to magnetic flux generated by valternating current, and two arms which are of high reluctance to iiuXl generated "by alternating current, said arms having equal reluctance to flux generatedby a contiuous flow of direct current, an armature for said magnet having two points of said bridge as its pole pieces. whereby when an alternating flux passes through said bridge, said pole pieces will be charged as opposite poles and attract said armature. l i

13. An electromagnet having a magnetic circuit. a portion of said magnetic circuit comprising a IVheatstone bridge having two arms which are of low 4reluctance to a magnetic iux generated by alternating current, and two arms which are of high reluctance to flux generated by alternating current, said arms having equal vreluctance to ux generated by a continuous How` ofidirectcurrent, an armature for said magnet. having two points of said bridge vas its pole pieces,

whereby when an alternating flux passes.

a'magnet, a magnetic cir-,

branches between said chokingmeans,

K other end direct current Alux passes through said bridge said armature will not be attracted.

14:. An electromagnet, a magnetic circuit for said magnet having a pair of parallel branches, means for causing a magnetic i'luX- to flow in said circuit7 means at one end oi' one of said branches for choking the lines ot' force insaid branch, and means near the other end of said other branch for choking the lines of Jforce in said other branch, an armature for said magnet, bridged across said Where by when the strength of said magnetic flux is rising in strength the lines of force are caused to iow through said arn'iature to attract the same. v

15. A magnetic circuit having parallel branches, vmeans for causing a magnetic flux to flow in said circuit, means at one end of one branch for opposing any change in strengthof said magnetic flux, means at the of the other branch for opposing any change in strength of said linx, a circuit controller forming a bridge across said parallel branches atl the mid-point thereof and out of engagement therewith, whereby v .any change in strength of said flux, a circuit controller forming a bridge across said parallel branches at the mid-point thereof and out of engagement therewith, whereby when said' magnetic flux is rising in strength said magnetic flux is caused to flow through said circuit controller to attract the same to said branches, and a circuit controlled by .said controller.

Signedlbi7 nie at Chicago, Cook county, Illinois, this first day of December, 191i'.

' JOHX ERICKSON.

for causlng a magnetic flux 

